resolved: add a DNS client stub resolver

Let's turn resolved into a something truly useful: a fully asynchronous
DNS stub resolver that subscribes to network changes.

(More to come: caching, LLMNR, mDNS/DNS-SD, DNSSEC, IDN, NSS module)

1 files changed, 84 insertions, 0 deletions

diff --git a/src/resolve/resolved-link.h b/src/resolve/resolved-link.h
new file mode 100644
index 0000000000..07f68ab41c
--- /dev/null
+++ b/src/resolve/resolved-link.h
@@ -0,0 +1,84 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "in-addr-util.h"
+#include "ratelimit.h"
+
+typedef struct Link Link;
+typedef struct LinkAddress LinkAddress;
+
+#include "resolved.h"
+#include "resolved-dns-server.h"
+#include "resolved-dns-scope.h"
+
+struct LinkAddress {
+        Link *link;
+
+        unsigned char family;
+        union in_addr_union in_addr;
+
+        unsigned char flags, scope;
+
+        LIST_FIELDS(LinkAddress, addresses);
+};
+
+struct Link {
+        Manager *manager;
+
+        int ifindex;
+        unsigned flags;
+
+        LIST_HEAD(LinkAddress, addresses);
+
+        LIST_HEAD(DnsServer, link_dns_servers);
+        LIST_HEAD(DnsServer, dhcp_dns_servers);
+        DnsServer *current_dns_server;
+
+        DnsScope *unicast_scope;
+        DnsScope *mdns_ipv4_scope;
+        DnsScope *mdns_ipv6_scope;
+
+        size_t mtu;
+
+        char *operational_state;
+
+        RateLimit mdns_ratelimit;
+};
+
+int link_new(Manager *m, Link **ret, int ifindex);
+Link *link_free(Link *l);
+int link_update_rtnl(Link *l, sd_rtnl_message *m);
+int link_update_monitor(Link *l);
+bool link_relevant(Link *l);
+LinkAddress* link_find_address(Link *l, unsigned char family, union in_addr_union *in_addr);
+
+DnsServer* link_find_dns_server(Link *l, DnsServerSource source, unsigned char family, union in_addr_union *in_addr);
+DnsServer* link_get_dns_server(Link *l);
+void link_next_dns_server(Link *l);
+
+int link_address_new(Link *l, LinkAddress **ret, unsigned char family, union in_addr_union *in_addr);
+LinkAddress *link_address_free(LinkAddress *a);
+int link_address_update_rtnl(LinkAddress *a, sd_rtnl_message *m);
+bool link_address_relevant(LinkAddress *l);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Link*, link_free);